How Bad Posture Causes Back Pain
In on this page, we will explain how bad posture and bad ergonomics at work can cause chronic strain to the ligaments of the back, and how this chronic stretching of the ligaments can cause back pain.
At the root of 90 percent of cases of all back pain are:
- The normal degenerative changes of the intervertebral discs.
- Changes to the facet joints due to normal wear and tear. The cartilage in the facet joints may wear out on their own, due to the aging process, or their rate of degeneration may be accelerated due to diminished lubrication, loss of disc height, weakened muscles, or sagging ligaments.
- Osteophytes (bony growths) around the borders of the facet joints and discs may cause irritation of the joints, and the nerves in the area may respond with back pain.
- Back pain may be caused by acute muscle strain or chronic weakness of the muscles.
How Bad Posture Causes Back Pain: All of the five factors mentioned above may be traced back to bad back posture. Bad posture may cause certain muscles groups to be used more often than others, causing not only a muscular imbalance but also weakness of the muscles in certain areas. When we sleep, sit, and stand, we have opposing muscles pulling on the spine in all directions. In a person with a healthy back, the muscles pulling the spine are in perfect balance, and the overall result is the spine being held in its ideal position, and with the spine retaining its healthy curvature among all its segments. In a person with chronically bad posture, some of the abdominal muscles or back muscles may be weaker than others, and opposing forces on one side of the spine are stronger than opposing forces on the other side of the spine, and the spine may be thrown out of its perfect balance.
Muscle imbalances, and chronic strain of the ligaments caused by bad posture may cause back pain in a number of ways. Bad postural habits are particularly tough on the spinal ligaments that anchor the individual elements. The ligaments of the spine are designed to allow for some stretching, up to 25% in a young healthy spine. But the ligaments are not designed to be chronically strained, as would be the case of people slouching over their desk or sitting in chairs that offer poor lumbar support. When these ligaments become chronically strained, they may cause pain directly, or as a result of non-protection of the facet joints and discs of the back.
Ligaments contain pain receptors called nociceptors. When these ligaments are under chronic strain, these nociceptors may begin firing at a high enough rate that the brain responds in the form of sending out pain signals.
Poor posture strains the interspinous ligament, ligamentum flavum, supraspinous ligament, and longitudinal ligaments in the back. When someone sits hunched over for prolonged periods, the anterior longitudinal ligament will contract. This will cause the facets inside the facet joints to also become misaligned, leading to pain.